I remember when I was growing up (decades ago), my dad instilled in me to never put a magnet up to a computer or TV because they would cause irreparable damage to the screen. While I’m sure that SOMEWHERE out in the world there’s a magnet strong enough to cause damage if given enough time or whatever, but in terms of what I can buy from a store, would it be safe to keep my cell phone and a magnet (say, one of those ‘clicking’ fidget toys with half a dozen or so small magnets) in the same pocket, or am I just asking for trouble?
Edit: Thank you everyone for all your answers! I now know far more than I expected to from this silly question 😁
UNIX Neckbeard here:
Magnets use to affect the magnetic hard drives (spinning platter, HDD) that were inside computers. This was especially bad because it would erase data permanently. It was the main concern about magnet+computer that everyone was worried about. CRT monitors were affected by magnets, but the inbuilt degauss or a handheld degaussing coil would usually correct the issue.
If your device has solid state storage (basically everything nowadays) that concern went away. Any other issues (like affecting the compass or accelerometer in a phone) are only temporary.
I have never heard of a magnetic field damaging an LCD and a quick google search says that’s a myth. Pressing on an LCD will damage it, so maybe a really strong magnet that was placed on an LCD that had ferrous metal behind it physically broke some LCDs and the myth was born, when really it was just pressure that broke the LCD.
I’m always wary of stacking hard drives together because they have magnets in them, but at the same time, they’re designed to be stacked. I guess I worry more about loose external drives.
So I guess you just need a really strong magnet to cook the device by induced current